Not sure if I'm supposed to be touting eBay auctions here (even tho it's not my item)-- but I recommend this book. It's skinny (maybe a centimeter thick), but it's a good handy summary of airliners since WWII. If you want to know the lengths of the different DC-9s, or the date of the first airline service for the 737-200, or about now-forgotten airliners like the Languedoc, this is a good first place to look.